The invention relates to dairy equipment, and more particularly to milking claws.
A milking claw is part of a milking cluster which is an assembly attached to the dairy animal's udder during milking. The cluster includes the claw, four shell assemblies, four short milk tubes, four air tubes, and an air fork, for example as shown in U.S. Pat. No. 5,586,518, incorporated herein by reference. Each shell assembly includes an outer shell or teat cup, and an elastic inner liner called a teat cup liner or inflation. The short milk tube connects the teat cup shell assembly to the claw which in turn is connected to a milk transport hose subject to vacuum or negative pressure. The air tube connects the space between the teat cup liner and the shell to the air fork. The air fork is connected through one or more air lines to a pulsation device cycling vacuum off and on.
When milking a dairy animal, the inside bore of the teat cup liner is at the system vacuum level, and the space between the teat cup liner and the shell is either at vacuum or at atmospheric pressure, depending on the cycle of the pulsation device. When there is atmospheric pressure on the outside of the liner in the space between the liner and the shell, the vacuum on the inside of the liner causes the liner to collapse. This is known as the rest phase, during which there is no milk flow, i.e. the liner is closed. When there is vacuum on the outside of the liner in the space between the liner and the shell, such vacuum balances the vacuum on the inside of the liner, and the liner can relax or expand. This is the milk phase, during which milk flows, i.e. the liner is open. Most milking clusters operate efficiently with pulsation rates between 45 and 60 cycles per minute. The pulsing movement of the liner massages the teat. In the rest phase, the collapse of the liner squeezes the teat, forcing blood in the teat to circulate. Without this rest phase, blood would not circulate throughout the teat, and injury to the teat might result. Milk from the four teat cup assemblies flows into the milking claw, and then through the claw outlet to a collection facility, as is known.
The present invention relates to an improved milking claw, including an improved claw top.